ابحث في الدعم

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Issue with adblocker working on restart & not saving some prefs

more options

First issue: Adblocker works fine when first installed. Then if FF is shut and opened again it SAYS it's enabled but it doesn't do anything. I have to go into the addon menu to disable and enable it to get working again, when it works fine. It's just really annoying having to do this. Certain the issue is with FF not adblocker.

Second: FF will not save preferences involving ticking a 'do not show this message again' box, i.e. with closing multiple tabs, private browsers, etc. All other prefs save fine. And yes, I've read the FF won't save prefs article and tried all that;l it doesn't work.

First issue: Adblocker works fine when first installed. Then if FF is shut and opened again it SAYS it's enabled but it doesn't do anything. I have to go into the addon menu to disable and enable it to get working again, when it works fine. It's just really annoying having to do this. Certain the issue is with FF not adblocker. Second: FF will not save preferences involving ticking a 'do not show this message again' box, i.e. with closing multiple tabs, private browsers, etc. All other prefs save fine. And yes, I've read the FF won't save prefs article and tried all that;l it doesn't work.

الحل المُختار

If you do not keep changes after a restart then see:


Create a new profile as a test to check if your current profile is causing the problems.

See "Creating a profile":

If the new profile works then you can transfer some files from an existing profile to the new profile, but be careful not to copy corrupted files.

Read this answer in context 👍 0

All Replies (10)

more options

You can check for problems with preferences and try to rename or delete the prefs.js file and possible numbered prefs-##.js files and a possible user.js file to reset all prefs to the default values.


You can try to reset Firefox.

If you reset Firefox then a new profile is created and some of your data (bookmarks, passwords, cookies, form data) is automatically imported and your current profile will be moved to the desktop (Old Firefox Data).

You can recover more data from the old profile (be cautious with doing that).

more options

Reset didn't work.

Deleted prefs.js file but didn't make a difference. No user file.js present.

Thanks for response.

more options

You can look at these warn prefs on the about:config page and possibly toggle their value via the right-click context menu or double click with the left mouse button.


It is possible that there is a problem with the file(s) that store the extensions registry.

Delete the files extensions.* (e.g. extensions.sqlite, extensions.ini, extensions.cache) and compatibility.ini in the Firefox profile folder to reset the extensions registry.

New files will be created when required.

See "Corrupt extension files":

If you see disabled, not compatible, extensions in "Tools > Add-ons > Extensions" then click the Tools button at the left side of the Search Bar (or click the "Find Updates" button in older Firefox versions) to check if there is a compatibility update available.

If this hasn't helped then also try to delete the addons.sqlite file.


Create a new profile as a test to check if your current profile is causing the problems or try to reset Firefox.

See "Creating a profile":

If the new profile works then you can transfer some files from an existing profile to the new profile, but be careful not to copy corrupted files.

more options

Afraid none of the things above fix either problem.

When changing the values in the about:config for the pop warning boxes, they don't pop up when closing that session. But when I next open FF, they've reset to default.

more options

الحل المُختار

If you do not keep changes after a restart then see:


Create a new profile as a test to check if your current profile is causing the problems.

See "Creating a profile":

If the new profile works then you can transfer some files from an existing profile to the new profile, but be careful not to copy corrupted files.

more options

New profile doesn't help. Neither does clean reinstall.

Think I've tried everything in the pref not saved article. Have no of the other software installed it lists.

Scanned computer with Malwarebytes; nothing.

more options

Is this about Adblock Plus or another extension?

Make sure that have subscribed to a Filter list (e.g. the EasyList).

Adblock Plus forum:

more options

Had to create a profile as FF was refusing to open today. Which fixed that issue but it also fixed the two issues detailed above - which is strange because when I created a new profile before and the issue sustained.

Anyway for the time being things seemed fixed now. Thanks for the help.